The present invention relates to an apparatus for cooking an egg using microwave radiation.
Preparing an egg by boiling the egg in water of about 100 degrees Celsius usually takes about 3.5-4 minutes for a so called soft-boiled egg, i.e. an egg having solid albumin or egg white and warm but substantially liquid yolk. Furthermore, usually the water needs to be heated to the required temperature, which takes additional time. Many methods and apparatus have been proposed for properly boiling an egg more swiftly. Some of these methods use microwave radiation. When using a microwave oven for cooking an egg as such, the egg may explode inside the oven or, even worse, in the hands or face of the consumer. Thus, methods were devised for cooking an egg in a microwave oven while preventing the egg from exploding.
For instance, a method is proposed, in which an egg is first shelled and its contents are put in a small container, in which the egg is subsequently boiled in a conventional microwave oven in about 60 seconds. The end result often is a too hard or rubbery albumin. Often, the egg white is not cooked uniformly. In professional kitchens, the result of this method is not acceptable.
In another known method, the egg in unbroken state is placed in an electrically conducting holder filled with a small amount of water. The holder is subsequently placed in a conventional microwave oven. In about 4-5 minutes, an egg is cooked. The cooking time is not reduced, but it does require less time to boil the water first.
In EP-988795 an egg is placed in a container having walls which are transparent to microwave radiation. The container is filled with hot water of 90° C., and placed in a conventional microwave oven. Subsequently, the egg is placed in the container, and boiled in about 110 seconds.
In EP-992197, an apparatus is presented, in which an egg is boiled in a microwave field, while hot water is poured over an egg (shower).
These methods are complicated, and require additional devices or steps, and additional time to heat up the water.
EP-1.917.867 discloses a package for cooking an egg in a microwave oven. The package comprises a covering adapted to surround an egg, and is arranged to partially transmit microwave radiation and partially absorb microwave radiation. As an example, a medium sized egg is wrapped in a tissue, soaked in 20 ml 0.5M NaCl solution, and a rubber material was used for packaging. The package was placed in a regular commercial microwave oven and subjected to a heating program. This procedure of packaging is laborious and does not allow reproducible results, which is in particular important in consumer applications.
JP60126062 discloses a method for preparing an egg in a microwave oven, in which an egg is placed in a container with water containing 5 gr salt. When subjecting this to 500 W microwave radiation, a hard-boiled egg is prepared in about 390 sec. It is suggested that a soft-boiled egg can be prepared by increasing salt concentration. The suggested preparation time is still long, even longer than just preparing an egg in hot or boiling water. Furthermore, it requires the preparation of salt water with the right amount of salt added.